Added polyfill for Canvas for IE < 9.0.
Added polyfills to upgrade old browsers to EcmaScript 5.
Fixed bugs in WebGLTransparencyHitArea.
Also fixed a bug in DeerHuhn which forced the browser to use CanvasTransparencyHitArea.
WebGL possible memory leaks fixed.
Changed spritesheet to contain 1px border around the single sprites.
Reformatted TransparencyHitArea to conform to pixi.js contributing guide.
Refactored the representation of animals.
Reformatted deerhuhn.js.